A general problem in nanotechnology is the siting of nanoscale moieties (nanomoieties) in sparsely packed deterministically located sites on a substrate surface. This difficulty arises because the sizes of nanomoieties such as nanotubes, nanowires, nanorods, nanofibers, quantum dots, and nanoscale seed particles (nanoseeds) can be on the order of 1-10 nm, smaller than the size of the smallest site that can be created at a predetermined location by an available method comprising one of scanning probe lithography, dip pen nanolithography, electron beam lithography, focused ion beam lithography, X-ray lithography, photolithography, and the like.
Several means have been developed to provide stochastically located, densely packed arrays of nanomoieties on a substrate, among which is the use of diblock copolymers. These means typically result in a structure with some local order, comprising for example a hexagonal close-packed array of nanomoieties on a planar surface, but the packing of the nanomoieties in arrays is dense rather than sparse and the location of an individual nanoscale moiety (nanomoiety) is random with respect to an overall coordinate system. Additionally, such means are incompatible with the use of pre-made photolithographic masks (photomasks) to fabricate additional features, either before or after, on the same substrate at predetermined locations with are far apart compared to the size of an individual nanomoiety.
One example of the need for a method of creating sparse arrays of deterministically located nanomoieties is the fabrication of integrated electronic circuits using carbon nanotubes. It is known that an individual nanoscale transistor can be fabricated on an insulating substrate by placing an individual instance of a carbon nanotube on the substrate, its length disposed parallel to the substrate surface, and then defining gate, source, and drain electrodes atop the nanotube and atop the substrate by lithographic means. However, the placement of hundreds, thousands, millions, or more of nanotubes on one substrate at sparsely packed deterministic sites consistent with fixed photomask patterns used for fabrication of many electrodes is problematic.
Another example of the need for a method of creating sparse arrays of deterministically located nanomoieties is the placement of elements comprising one of nanoseeds, quantum dots, nanotubes, nanorods, nanowires, nanofibers, and the like at well-controlled sparsely packed locations for purposes such as use in electron emitters. The placement of multiple such elements is often problematic.
Thus there exists a need for a method of placing multiple nanomoieties at locations on a substrate.